1. Field of the Invention
The present invention relates to connection systems linking undersea acoustic antennas to electronic devices for interpreting acoustic signals. The electronic devices are situated within the hull of a submarine, while the antennas are situated outside the hull.
2. Background Art
The receiving antennas of sonars are generally situated outside a carrying vessel, a submarine for example, and are conventionally linked to electronic racks, which interpret the signals sent and received by these antennas, by electrical connections passing through the hull of the vessel. This arrangement entails numerous drawbacks, including a loss of leaktightness in the region of the connectors, a substantial number of cables, junction boxes, and pressure hull penetrators (PHP""s), very high wiring costs, a reduced reliability by reason of the large number of devices used to establish these electrical connections, and finally a risk of a rupturing the leaktightness of the hull when it is necessary to replace one of the sensors.
For example, if it were desired to link a cylindrical antenna including 128 columns of 16 hydrophones, i.e., 2048 channels, using them all to carry out processing in azimuth and in then it would be necessary, between the antenna and the PHPs, to use 128 connectors on the columns and on the cables, 128 cables formed by 18 screened pairs, and 128 connectors on the cables and on the PHPs, i.e., 512 submerged connectors in total. As regards the PHPs, it would also be necessary to use 32 cables of 18 screened pairs fitted with 2 times 32 sockets, each socket including 4 connectors, 32 electronics boxes for conditioning the signals, and 32 cables fitted with 2 times 32 sockets for linking these conditioning boxes to the electronic rack.
Such an embodiment cannot be implemented in practice, by reason of the cost of the cabling, of the weight of the cables and connectors, which would be of the order of 6 tons, and of the very large number of PHPs and submerged connectors.
In order to use an antenna of this type, which is very useful for fine position-fixing of the sources of acoustic noise, and in order to overcome these drawbacks, the invention proposes a connection system for underwater acoustics. The connection system includes: elements of an antenna embedded in a leaktight first block of the system; a first part of a divisible transformer embedded in the first block, the first part electrically connected to the elements of the antenna; a second part of the divisible transformer embedded in a leaktight second block of the system, the second part magnetically continuous with the first part; and an electro-optical transmitter embedded in the second block and electrically connected to the second part. The first and second blocks are separated from one another, and the divisible transformer communicates signals from the elements of the antenna to the electro-optical transmitter without compromising the leaktightness of the first or second block.
According to another aspect of the invention, the electro-optical transmitter is a vertical cavity surface emitting laser (VCSEL).
Other features and advantages of the invention will become clearly apparent from the following description, given by way of non-limiting example with regard to the annexed figures.